The needle in your sewing machine can make all the difference when sewing your next project. How do you know what needle to use for what fabric? It is actually much simpler than you think!
A dull or incorrect needle can cause skipped stitches, pulls and snags or cause the seam to scrunch up. These problems are so frustrating but can easily be diminished or even eliminated by changing your needle.
To determine what kind of needle you require for the fabric you are using you first need to look at the size of your needle. If you only have a pack of "universal needles" than this is the only step you need to take. Universal needles usually come with the sewing machine and can be used for nearly every fabric IF you choose the correct size.
Exhibit A: The Universal needle. You can use this needle for nearly any type of fabric but wait...what are those numbers for!?
The needle size is indicated by the 2 numbers (60/8 for example). These numbers tell you exactly the same thing but one is the metric size (60, on the first needle case) and one is the imperial size (8, on the same case). I have no idea why they have to list the metric and imperial sizes, but all needles do.
Choosing what size you need to easy. Needles range from 60/8 to 120/20. The bigger then number, the larger the diameter of the needle. The larger diameter means that these needles are stronger but obviously bigger. If you are sewing very sheer or netted fabrics choose the smallest diameter needle you have. If you are sewing heavy denim, upholstery, or vinyl then choose the largest diameter needle you have. It is just that easy. If you only have money to purchase one universal needle then go for the 80/12 which is good for cottons and most other medium weight fabrics.
Now that you are a pro at picking a needle size let us move on to specialty needles.
Exhibit B: Needles for specific fabrics.
What?! Have you never tried one of these? Then you are missing out. These needles are designed just to make your life easier (really). Most everyone has probably seen the ubiquitous Jersey (or stretch, or ball point) needle. However, there are needles for silks and other fine fabrics (microtex or sharps), Jeans, embroidery and quilting.
I want to stop for a moment and point out the 130/705 H on the bottom of the schmetz needle cases. This number indicates that this needle is for a sewing machine that has a needle system of 130/705 H. Basically every home sewing machine uses this system so some companies don't even place it on their needle cases anymore.
The letter after the H is important though as this indicates the needle type.
SUK = knitted fabric needles
S = Stretch fabric needles
*I use these interchangeably however SUK is for lycra and knitted fabrics and S if for elastic, t shirt knits and jersey.
M = microfiber and silks
J = jeans
E = Embroidery
Q = quilting.
Each of these types of needle have a specific design to help you sew certain types of fabrics. Stretch needles have ball points to prevent snagging. Microtex (sharps) have very sharp and pointy tips to help with sewing silks and microfibers.
Some of these specialty needles are harder to find but they are very useful. I primarily sew fine silks and can not do this without my microtex needle. The silks will get pulls and puckers in them if I use a universal needle. I also change out my needle often as a dull needle will cause similar problems. Remember to choose a needle size that works with the weight of the fabric you are sewing. These specialty needles also come in a range of sizes.
Finally we have the twin needle: Exhibit C: Twin needles
These needles are often elusive. If you find one at a chain fabric store you will not have many sizes to choose from. Both these are size 80 needles but the first has the needle points 3mm apart and the second has them 2mm apart. The "ZWI" on the Schmetz needle case indicates it is a double needle. A "Drei" indicates a triple needle, although I have never seen one of these.
Double needles are perfect for finishing seams on knits and accessories, such as pillows or bags. This double stich seam makes these items look very professional. I prefer at least a 3mm gap between the two needles but sometimes you just have to go with what you find in the store.
I hope that this makes it easier to understand the markations you see on needle cases and helps you choose the correct needle next time you begin a project.